Red Bull team principal Christian Horner says he is not yet ready to drop his complaints about Mercedes' wing design, despite it being deemed legal by Formula One officials.

Red Bull and Lotus queried the Mercedes design in Australia but FIA technical delegate Charlie Whiting ruled it within the rules. The queries continued at the Malaysian Grand Prix.

Horner said Friday that "the car has passed scrutineering so you have to assume the FIA is happy," but when asked if he would drop the issue, Horner said "probably not", adding "it would be nice to come out of this weekend with that clarity."

The Mercedes rear wing has ducts that become exposed when the wing flaps are open, channeling air back toward the front wing.

The legality of the system has been challenged because it only becomes operational when the car's Drag Reduction System (DRS) is engaged.

Since the DRS is engaged by the driver, teams have argued that the system is not passive, but driver operated, which is not permitted in F1.